<PAGE>

                                                                    Exhibit 3(o)
                         CERTIFICATE OF INCORPORATION

                                      OF

                        GLOBAL TRADE & INVESTMENT, INC.


Section 1.01.  Name.  The name of the Corporation is Global Trade & Investment,
------------   ----
Inc.

Section 2.01.  Registered Office and Agent.  The registered office of the
------------   ---------------------------
Corporation in the State of Delaware is located at 1013 Centre Road, Wilmington,
County of New Castle. Its registered agent at such address is Corporation
Service Company.

Section 3.01.  Purposes.  The purposes of the Corporation are:
------------   --------

          (a)  to engage in the business of providing consulting and information
               services for international trade related matters;
          (b)  to purchase, sell, lease, trade, hold, license, grant rights in
               or with respect to, and manage property (both real and personal,
               tangible and intangible) assets and rights;
          (c)  to provide services of any kind or nature, to third parties and
               affiliates; and
          (d)  to engage in any lawful act or activities for which corporations
               may be organized under the General Corporation law of Delaware.

Section 4.01.  Authorized Shares.  The total number of shares of stock which the
------------   -----------------
Corporation shall have authority to issue is one thousand (1000) shares of
common stock having a par value of $1.00 per share and entitled to vote at any
annual or special meeting of the stockholders of the Corporation.

Section 5.01.  Incorporator.  The name and mailing address of the incorporator
------------   ------------
is: Mark E. Mazo, 1001 Pennsylvania Avenue, N.W., Washington, D.C. 20004.

Section 5.01.  Duration.  The Corporation is to have perpetual existence.
------------   --------

Section 6.01.  Initial Board of Directors.  The names and mailing addresses of
------------   --------------------------
the persons who are to serve as directors of the Corporation until the first
annual meeting of stockholders or until their successors are elected and qualify
are:

     Mr. Douglas W. McMinn                      1850 K Street, N.W.
                                                Washington, D.C.  20006

     Mr. Nicholas Burakow                       1850 K Street, N.W.
                                                Washington, D.C.  20006

     James O. Edwards                           9300 Lee Highway
                                                Fairfax, Virginia  22031

     Raymond E. List                            9300 Lee Highway
                                                Fairfax, Virginia  22031

The powers of the incorporator shall  terminate upon the filing of this
Certificate of Incorporation.

Section 7.01.  Limitation of Liability.
-------------  -----------------------

          (a)  No person shall be liable to the Corporation for any loss or
damage suffered by it on account of nay action taken or omitted to be taken by
him as a director of officer of the Corporation, if such person (i) in good
faith exercised or used the same degree of diligence, care and skill as an
ordinarily prudent man would have exercised or used under similar circumstances,
or (ii) took, or omitted to take, such action in good faith reliance upon advice
of counsel for the Corporation, or upon books of account or reports made to the
Corporation by any of its officers or by an independent certified public
accountant, or by an appraiser selected with reasonable care by the Board of
Directors or by any committee designated by the Board of Directors, or in good
faith reliance upon other records of the Corporation.

          (b)  No director of the Corporation shall be liable to the Corporation
or its stockholders for monetary damages for breach of fiduciary duty as a
director, provided that the foregoing shall not eliminate or limit the liability
of a director (i) for any breach of the director's duty of loyalty to the
Corporation or its stockholders, (ii) for acts or omissions not in good faith or
which involve intentional misconduct or a knowing violation of law, (iii)
<PAGE>

under Section 174 of the Delaware General Corporation Law, or (iv) for any
transaction from which the director derived an improper personal benefit.

Section 8.01.  Ratification by Stockholders.  Any contract, transaction or act
-------------  ----------------------------
of the Corporation, the Board of Directors, or a committee of the Board of
Directors which shall be approved or ratified by a majority of a quorum of the
stockholders entitled to vote at any meeting or, without a meeting, by the
written consent of the holders of a majority of the stock entitled to vote,
shall be as valid and binding as though approved or ratified by every
stockholder of the Corporation; but any failure or the stockholders to approve
or ratify such contract, transaction or act, when and if submitted, shall not be
deemed in any way to invalidate the same or to deprive the Corporation, its
directors or officers, of their right to proceed with such contract, transaction
or act.

Section 9.01.  Indemnification of Directors and Officers for Actions, Suits, or
-------------  ----------------------------------------------------------------
Proceedings Other than by or in the Right of the Corporation.  To the full
------------------------------------------------------------
extent permitted by law, the Corporation shall indemnify any person who was or
is a party or is threatened to be made a party to any threatened, pending or
completed action, suit or proceeding, whether civil, criminal, administrative or
investigative (other than an action by or in right of the Corporation), by
reason of the fact that he is or was or has agreed to become a director or
officer of the Corporation or is or was serving or has agreed to serve at the
request of the Corporation as a director or officer of another corporation,
partnership, joint venture, trust or other enterprise (including employee
benefit plans), or by reason of any action alleged to have taken or omitted in
such capacity, against costs, charges, expenses (including attorneys' fees),
judgments, fines and amounts paid in settlement actually and reasonably incurred
by him or on his behalf in connection with any threatened, pending or completed
action, suit or proceeding and any appeal therefrom including but not limited to
liability and expenses incurred on account of profits realized by him in the
purchase or sale of securities of the Corporation, if and only if he acted in
                                                   --------------
good faith and in a manner he reasonably believed to be in or not opposed to be
best interests of the Corporation, and, with respect to any criminal action or
proceeding, had no reasonable cause to believe his conduct was unlawful; the
termination of any action, suit or proceeding by judgment, order, settlement,
conviction, or upon a plea of nolo contendere or its equivalent, shall not, of
                              ---- ----------
itself, create a presumption that the person did not act in good faith and in a
manner which he reasonably believed to be in or not opposed to the best
interests of the Corporation, and, with respect to any criminal action or
proceeding, had reasonable cause to believe that his conduct was unlawful.

Section 9.02.  Indemnification of Directors and Officers for Actions or Suits by
-------------  -----------------------------------------------------------------
or in the Right of the Corporation.  To the full extent permitted by law, the
-----------------------------------
Corporation, in the sole discretion of the Board of Directors of the
Corporation, may indemnify any person who was or is a party or is threatened to
be made a party to any threatened, pending or completed action or suit by or in
the right of the Corporation to procure a judgment in its favor by reason of the
fact that he is or was or has agreed to become an employee, agent or contractor
of the Corporation, or is or was serving or has agreed to serve at the request
of the Corporation as a director, officer, employee, agent or contractor of
another corporation, partnership, joint venture, trust or other enterprise
(including employee benefit plans), or by reason of any action alleged to have
been taken or omitted in such capacity, against costs, charges and expenses
(including attorneys' fees) actually and reasonably incurred by him or on his
behalf in connection with the defense or settlement of any threatened, pending
or completed action or suit and any appeal therefrom, or the defense or
settlement of any claim, issue or matter, if and only if he acted in good faith
                                          --------------
and in a manner he reasonably believed to be in or not opposed to the best
interests of the Corporation except that no indemnification shall be made in
respect of any claim, issue or matter as to which such person shall have been
adjudged to be liable to the Corporation unless and only to the extent that the
Court of Chancery of Delaware or the court in which such action or suit was
brought shall determine upon application that, despite the adjudication of such
liability but in view of all the circumstance of the case, such person is fairly
and reasonably entitled to indemnity for such costs, charges and expenses which
the Court of Chancery or such other court shall deem proper.

Section 9.03.  Indemnification of Others for Actions, Suites, or Proceedings
-------------  -------------------------------------------------------------
Other Than By or In the Right of the Corporation.  To the full extent permitted
------------------------------------------------
by law, the Corporation, in the sole discretion of the Board of Directors of the
Corporation, may indemnify any person who was or is a party or is threatened to
be made a party to any threatened, pending or completed action, suit or
proceeding, whether civil, criminal, administrative or investigative (other than
an action by or in the right of the Corporation), by reason of the fact that his
or she is or was or has agreed to become an employee, agent or contractor of the
Corporation, or is or was serving or has agreed to serve at the request of the
Corporation as a director, officer, employee, agent or contractor of another
corporation, partnership, joint venture, trust or other enterprise (including
employee benefit plans), or by reason of any action alleged to have been taken
or omitted in such capacity, against cost, charges, expenses (including
attorneys' fees), judgments, fines and amounts paid in settlement actually and
reasonably incurred by him or her or on his or her behalf in connection with any
threatened, pending or completed action, suit or proceeding and any appeal
therefrom, including but not limited to liability and expenses incurred on
account of profits realized by him or her in the purchase or sale of securities
of the Corporation, if and only if he or she acted in good faith and in a manner
                    --------------
he or she reasonably believed to be in or not opposed to the best interests of
the Corporation, and, with respect to any criminal action or proceeding, had no
reasonable cause to believe his conduct was unlawful; the termination of any
<PAGE>

action, suit or proceeding by judgment, order settlement, conviction, or upon a
pleas of nolo contendere or its equivalent shall not, of itself, create a
         ---- ----------
presumption that the person did not act in good faith and in a manner which he
or she reasonably believed to be in or not opposed to the best interests of the
Corporation, and, with respect to any criminal action or proceeding, had
reasonable cause to believe that his conduct was unlawful.

Section 9.04.  Indemnification of Others for Actions or Suits By or In the Right
-------------  -----------------------------------------------------------------
of the Corporation.  To the full extent permitted by law, the Corporation, in
------------------
the sole discretion of the Board of Directors of the Corporation, may indemnify
any person who was or is a party or is threatened to be made a party to any
threatened, pending or completed action or suit by or in the right of the
Corporation to procure a judgment in its favor by reason of the fact that he or
she is or was or has agreed to become an employee, agent or contractor of the
Corporation, or is or was serving or has agreed to serve at the request of the
Corporation as a director, officer, employee, agent or contractor of another
corporation, partnership, joint venture, trust or other enterprise (including
employee benefit plans), or by reason of any action alleged to have been taken
or omitted in such capacity, against cost, charges, expenses (including
attorneys' fees)  actually and reasonably incurred by him or her or on his or
her behalf in connection with the defense or settlement of any threatened,
pending or completed action or suit and any appeal therefrom, or the defense or
settlement of any claim, issue or matter, if any only if he or she acted in good
                                          --------------
faith and in a manner he or she reasonably believed to be in or not opposed to
the best interests of the Corporation except that no indemnification shall be
made in respect of any claim, issue or matter as to which such person shall have
been adjudged to be liable to the Corporation unless and only to the extent that
the Court of Chancery of Delaware or the court in which such action or suit was
brought shall determine upon application that, despite the adjudication of such
liability but in view of all the circumstances of the case, such person is
fairly and reasonably entitled to indemnity for such costs, charges and expenses
which the Court of Chancery or such other court shall deem proper.

Section 9.05.  Indemnification for Costs, Charges and Expenses of Successful
-------------  -------------------------------------------------------------
Party.  Notwithstanding the other provisions of this Certificate, to the extent
-----
that a director or officer of the Corporation has been successful on the merits
or otherwise, including, without limitation, the dismissal of an action without
prejudice, in defense of any action, suit or proceeding referred to above, or in
defense of any claim, issue or matter therein, he shall be indemnified against
all costs, charges and expenses (including attorneys' fees) actually and
reasonably incurred by him or on his behalf in connection therewith.

Section 9.06.  Determination of Right to Indemnification.  Unless other wise
-------------  -----------------------------------------
ordered by a court, any indemnification under Sections 9.01 through 9.04,
herein, shall be paid by the Corporation unless a determination is made (1) by
the Board of Directors by a majority vote of a quorum consisting of directors
who were not parties to such action, suit or proceeding, or (2) if such a quorum
is not obtainable, or, even if obtainable a quorum of disinterested directors so
directs, by independent legal counsel in a written opinion, or (3) by the
stockholders, that indemnification of an individual entitled to indemnification
under Section 9.01 through 9.04, herein, is not proper in the circumstances
because he has not met the applicable standard of conduct set forth in Section
9.01 through 9.04, herein.

Section 9.07.  Advance Payment of Costs, Charges and Expenses.  To the full
-------------  ----------------------------------------------
extent permitted by law, the Corporation shall, upon request, pay costs, charges
and expenses (including attorneys' fees) incurred by a person entitled to
indemnification pursuant to Sections 9.01 and 9.02, therein, and, if applicable,
pursuant to Sections 9.03 and 9.04, herein, in defending a civil or criminal
action, suit or proceeding in advance of the final disposition of such action,
suit or proceeding; provided, however, that the payment of such costs, charges
and expenses incurred by a director or officer in his capacity as a director or
officer (and not in any other capacity in which service was or is rendered by
such person while a director or officer) in advance of the final disposition of
such action, suit or proceeding shall be made only upon receipt of an
undertaking by or on behalf of the director or officer to repay all amounts so
advanced in the event that it shall ultimately be determined that such director
or officer is not entitled to be indemnified by the Corporation as authorized in
this certificate; such costs, charges and expenses incurred by other employees,
agents and contractors may be so paid upon such terms and conditions, if any, as
the Board of Directors deems appropriate.

Section 9.08.  Procedure for Indemnification.  Any indemnification or advance of
-------------  -----------------------------
costs, charges and expenses provided for in Sections 9.01 through 9.07, herein,
shall be made promptly, and in any event within sixty days, upon the written
request of the person entitled to indemnification; the right to indemnification
or advances as granted by this Certificate shall be enforceable by a director of
officer in any court of competent jurisdiction.  If the Corporation denies such
request, in whole or in part, or if no disposition thereof is made within sixty
days, such person's costs, charges and expenses incurred in connection with
successfully establishing his right to indemnification, in whole or in part, in
any such action shall also be indemnified by the Corporation; it shall be a
defense to any such action (other than an action brought to enforce a claim for
the advance of costs, charges and expenses pursuant to Section 9.07, herein,
where the required undertaking, if any, has been received by the Corporation)
that the claimant has not met the standard of conduct set forth in Sections 9.01
through 9.04, herein, but the burden of proving such defense shall be on the
Corporation.  Neither the failure of the Corporation
<PAGE>

(including its Board of Directors, its independent legal counsel, and its
shareholders) to have made a determination prior to the commencement of such
action that indemnification of the claimant is proper in the circumstances
because he has met the applicable standard of conduct set forth in Sections 9.01
through 9.04, herein, not the fact that there has been an actual determination
by the Corporation (including its Board of Directors, its independent legal
counsel, and its shareholders) that the claimant has not met such applicable
standard of conduct, shall be a defense to the action or create a presumption
that the claimant has not met the applicable standard of conduct.

Section 9.09.  Authorization of Corporation Officers.  The proper officers of
-------------  -------------------------------------
the Corporation are, and each of them acting without the other is, authorized to
take any action, for and in the name of the Corporation, which he deems
necessary or appropriate (as conclusively presumed from the taking of such
action) to carry out and effect the foregoing Sections 9.01 through 9.08.

Section 9.10.  Other Rights; Continuation of Right to Indemnification.  The
-------------  ------------------------------------------------------
indemnification and advancement of expenses provided by this Certificate shall
not be deemed exclusive of any other rights to which a person seeking
indemnification or advancement of expenses may be entitled under any law
(present or future, common or statutory), by-law, agreement, vote of
stockholders or disinterested directors or otherwise, both as to action in his
official capacity and as to action in another capacity while holding office or
while employed by or acting as agent for the Corporation, and shall continue as
to a person who has ceased to serve in the capacity making him eligible for
indemnification, and shall inure to the benefit of the estate, heirs, executors
and administrators of such person; all rights to indemnification under this
Certificate shall be deemed to be a contract between the Corporation and each
director and officer of the Corporation who serves or served in such capacity at
any time while this Certificate as well as the relevant provisions of the
Delaware General Corporation Law or any other applicable laws are or were in
effect; any repeal or modification hereof or of such provisions of such law
shall not in any way diminish any rights to indemnification of such director or
officer entitled to indemnification or the obligations of the Corporation
arising hereunder.

Section 9.11.  Savings Clause.  If this Certificate or any portion hereof shall
-------------  --------------
be invalidated on any ground by any court of competent jurisdiction, then the
Corporation shall nevertheless indemnify each director and officer, and may
indemnify any other person entitled to indemnification, as to costs, charges and
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement with respect to any action, suit or proceeding, whether civil,
criminal, administrative or investigative, including as action by or in the
right of the Corporation, to the full extent permitted by any applicable portion
of this Certificate that shall not have been invalidated and to the full extent
permitted by applicable law.  To the full extent permitted by law, the
Corporation may enter into and perform agreements with persons, including,
without limitation, present and former officers, directors and employees of the
Corporation and of companies acquired by or merged with the Corporation,
obligating the Corporation, among other things, to provide indemnification and
advancement of costs, charges and expenses to such persons in addition to any
indemnification or advancement which may be available to such person under
Section 9.01 through 9.10 of this Certificate.

Section 9.12.  Insurance.  The Board of Directors may cause the Corporation to
-------------  ---------
purchase and maintain insurance on behalf of any person who is or was or has
agreed to become a director or officer of the Corporation, or is or was serving
at the request of the Corporation as a director or officer of another
corporation, or as its representative in a partnership, joint venture, trust or
other enterprise, including employee benefit plans, against any liability
asserted against such person and incurred in any such capacity or arising out of
such status, whether or not the Corporation would have the power to indemnify
such person.

Section 9.13.  Adoption of By-laws.  The Board of Directors may from time to
-------------  -------------------
time adopt By-laws with respect to indemnification and may amend such By-laws to
provide at all times the fullest indemnification permitted by the General
Corporation Law of the State of Delaware.

Section 10.01.  Settlement of Debts.  Whenever a compromise or arrangement is
--------------  -------------------
proposed between this Corporation and its creditors or any class of them and/or
between this Corporation and its stockholders or any class of them, any court of
equitable jurisdiction within the State of Delaware may, on the application in a
summary way of this Corporation or of any creditor or stockholder thereof or on
the application of any receiver or receivers appointed for this Corporation
under the provisions of section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this Corporation under the provisions of section 291 of Title 8 of the
Delaware Code, order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this Corporation, as the case may
be, to be summoned in such manner as the said court directs.  If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
Corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this Corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this Corporation, as the case may be,
and also on this Corporation.
<PAGE>

Section 11.01.  Elections of Directors.  Elections of directors need not be by
--------------  ----------------------
written ballot unless the By-laws of the Corporation shall so provide.

Section 12.01.  Stockholders Meetings, Records.  Stockholders meetings may be
--------------  ------------------------------
held within or without the State of Delaware, as the By-laws may provide.  The
books of the Corporation may be kept (subject to any provision in the General
Corporation Law of the State of Delaware) outside of the State of Delaware at
such place or places as may be designated from time to time by the Board of
Directors (or duly authorized committee of the Board of Directors) or in the By-
laws of the Corporation.

Section 13.01.  By-laws.  The Board of Directors (or a duly authorized committee
--------------  -------
of the Board of Directors) of the Corporation shall have the power to make,
alter or repeal its By-laws.

Section 14.01.  Amendment of Certificate of Incorporation.  The Corporation
--------------  -----------------------------------------
reserves the right to amend, alter, change or repeal any provision contained in
this certificate, in the manner now or hereafter prescribed by the General
Corporation Law of the State of Delaware, and all rights conferred upon
stockholders herein are granted subject to this reservation.


          IN WITNESS WHEREOF the undersigned, being the incorporator
hereinbefore named, for the purpose of forming a corporation pursuant to the
General Corporation Law of the State of Delaware, does make this certificate
hereby declaring and certifying that this is my act and deed and the facts
herein stated are true, and accordingly have hereto set my signature this 8th
day of December, 1987.



                                         Mark E. Mazo


District of Columbia:

          BE IT REMEMBERED that on 8th December, 1987, personally came before
me, a Notary Public for the District of Columbia, Mark E. Mazo, the subscriber
to the foregoing Certificate of Incorporation, known to me personally to be
such, and acknowledged the said Certificate to be his act and deed and that the
facts therein stated are truly set forth.

          GIVEN under my hand and seal of office the day and year aforesaid.

                                         Notary Public